A conventional twinkling light string includes a main wire connecting with several branch strings, wherein each branch string is provided several bulb assemblies. Every bulb assembly connected on a first string has the same structure, which is different from the bulb assembly on a nearby second string. Hence, the twinkling light string can effectively twinkle in use.
In order to obtain the above purpose, a known structure, such as U.S. Pat. No. 6,474,841, provides two kinds of bulb assemblies for use. It includes a standard bulb assembly and a non-standard bulb assembly being larger than the standard bulb for connecting with different branch strings in interval. When assembling the two kinds of bulb assemblies, it will be very trouble in differentiating them.
Accordingly, the present invention is to provide a twinkling light string, which is provided with two kinds of improved bulb assemblies while the bulb assemblies can be differentiated easily and assembled.